Stress (for example, water deficit, cold, heat, salt, pest, disease, or nutrient stress), can have adverse effects on plants such as yield reductions, increased susceptibility to disease and pests, reduced plant growth, and reproductive failure. An object of this invention is to provide transgenic plants which can express genes to ameliorate the adverse effects of stress. Useful genes for expression under stress are genes which promote aspects of plant growth or fertility, genes which impart disease or pest resistance or tolerance, stress-responsive transcription factors, and the like.
As a non-limiting example, considering the complexity of water use in land plants, especially during conditions that produce water deficit, relatively few promoters specifically associated with this aspect of plant physiology have been identified. It would be of benefit to the art to increase the known number and variety of promoters involved in the response to stress (such as the response to water deficit, cold, heat, salt, pest, disease, or nutrient stress) in plants, particularly in economically important plants (such as crop plants, for example, maize), and even more particularly in plants experiencing such stress. It would be especially advantageous to identify promoters which can be used in directing the expression of genes which are beneficial to the plant when induced during conditions of stress (for example, induced under conditions of water deficit, while having low to no expression under adequately watered conditions).